Expanding boring-tool



(No Model.)

B. F. BEUGLER.

EXPANDING BORING TOOL. No. 462,789. Patented Nov. 10,1891.

UNITED STATES PATENT OFFICE.

EDWIN F. BEUGLER, OF BUFFALO, NEIV YORK, ASSIGNOR OF ONE-IIALF TO EDGAR T. IVARD, OF SI'IELDONVILLE, MASSACHUSETTS.

EXPANDING BORING-TOOL.

SPECIFICATION forming part of Letters Patent No. 462,789, dated November 10, 1891.

Application filed September 19, 1889. Serial No. 324,411. (No model.)

To all whom it may concern:

Be it known that I, EDWIN F. BEUGLER, a citizen of the United States, residing in Butfalo, in the county of Erie and State of New York, have invented certain new and useful Improvements in Expanding Boring-Tools, of which the following is a specification.

My invention relates to that class of expanding boring -tools in which the cutters are [0 adapted to be expanded when the cuttingedge is worn away by use or by grinding, whereby one set of cutters may be used for along time for boring holes of one size, all of which will be fully and clearly hereinafter described and claimed, reference being had to the accompanying drawings, in which- Figure 1 is a plan or top view of the device. Fig. 2 is a side elevation. Fig. 3 is a vertical longitudinal section in line CL 1), Fig. 1. Fig.

4 is a bottom view. Fig. 5is a detached side elevation of the cutter.

The tool-holder 1 is madein cylindrical form and is provided with a series of longitudinal grooves 2 to give room for the chips to pass through. At the lower portion is the usual taper shank 3, by which it is secured in the lathe or boring-n1achine,and at the end is the usual flattened portion 4: to prevent it from turning in the socket. At or near the top of 0 the holder is a transverse opening 5,in which the cutter 6 is closely fitted. The two cutters are formed of one piece of steel having the cutting-edges 7 8, the upper portions of which are rounded, as shown at 9. In the center of the cutters is a slot or opening 10, having the inclined sides 11. In the center of the top of the tool-holder is a set-screw 12, which passes into the transverse opening 5, and the tapering point of the set-screw passes into the top of the opening 10, fitting between its sides 11. The object of the set-screw 1:? is to expand or force the cutting-edges 7 and 8 outward when required, after which it is rigidly tightened in place by a jam-nut 13. It will be noticed that the cutter is made with a heavy or strong portion 14: below the opening 10, so that it requires considerable power from the set-screw 12 to spread the cutters; consequently they will spring back with a strong force when released from the set-screw. This construction is very important, as it keeps them rigid and steady, so that they will cut smoothly Without trembling. The shank or holder being of hardened steel furnishes a guide for them.

The operation will be readily understood from the foregoing description and drawings.

I claim as my invention- In an expanding boring-t0ol, the combination,with a cylindrical tool-holder having a series of side grooves extending longitudi- 6o nally the entire length of the enlarged portion of the holder and opposite the cutters to permit the chips to pass through, and a transverse opening through the front end of the holder to receive the cutter, of a double cutter having an opening 10, extending part way down, side cutting-edges 7 and 8, end cutting-edges 9, and a flat-back end adapted to rest against the side of the transverse open ing, and a taper-pointed screw and jain-nut 7: for expanding and securing the cutters in place, substantially as described.

EDWIA F. BEUGLER. Witnesses:

J AMES SANGSTER, ARTHUR J. SANGSTERJ 

